Alphabet input device and alphabet recognition system in small-sized keypad

ABSTRACT

Disclosed herein are an alphabet input device and an alphabet recognition system in a small-sized keypad. The device includes: a first keypad part comprising a plurality of buttons each of which is assigned with a symbol extracted from strokes of alphabet characters so that the alphabet characters be input by one of the buttons or a combination of two or more of the buttons; and a second keypad part comprising one or more buttons each assigned with an alphabet character having a high usage frequency. With the device, alphabet characters can be inputted in a simpler and more efficient manner.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of application Ser. No. 12/344,248, filed Dec. 25, 2008, which claims priority to Korean application number 10-2008-0067954, filed Jul. 14, 2008, which application are hereby incorporated by reference in these entirety for all purposes as if fully set forth herein.

BACKGROUND

1. Technical Field

The present disclosure relates to an alphabet input device and an alphabet recognition system in a small-sized keypad.

2. Related Art

English alphabet input devices widely used in most of small-sized keypads are provided with a toggle function. FIG. 1 is a diagram illustrating the arrangement structure of such a keypad with a toggle function. As described in FIG. 1, the keypad is composed of a plurality of buttons formed in 4.times.3 matrix, in which two to four alphabets are disposed in each of the buttons.

To input alphabets with the toggle function, however, a user must be aware of positions of keys and toggle order and must push buttons many times in certain cases. Furthermore, when the user wants to input alphabets in the same button by permutation, it must wait for a predetermined time to input a subsequent character or press a movement button. As a result, the efficiency of the input process is reduced.

In order to solve the problems, various methods of inputting alphabet have been proposed, for example, as disclosed in Korean Patent Application Publication No. 10-2006-29430, Korean Patent Application Publication No. 2002-55833, and Korean Utility Model Registration No. 20-0419301. FIG. 2 shows the configurations of the alphabet input devices disclosed in the above references. In the alphabet input devices, an alphabet character is input using a combination of character keys.

The alphabet input devices, however, have a problem of an ambiguity occurring in the analysis of the input permutation of certain combination of characters. For example, in case of the device of Korean Patent Application Publication No. 10-2006-29430, F is input by a combination of ‘|’ and ‘-’, and T is input by a combination of ‘-’ and ‘|’. If a user types a combination character permutation of ‘|’, ‘-’, and ‘|’ to input IT, the combination character permutation may be recognized as FI as well as TI due to the ambiguity of analysis. In case of the device of Korean Utility Model Registration No. 20-0419301, V is input by ‘V’, I is input by ‘|’, and Y is input by a combination of ‘V’ and ‘|’. If a user types ‘V’ and ‘l’ to input Y, this may be also recognized as VI. A similar ambiguity occurs in the device of Korean Patent Application Publication No. 2002-55833.

In order to solve the ambiguity, like the devices with toggle function, the devices with combination function still require an automatic time delay acting as a separator or a movement button.

On the other hand, the prior art technologies do not take into consideration usage frequency of each alphabet character in the design of the input methods and system.

The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.

SUMMARY

Embodiments of the present invention are directed to provide an alphabet input device and an alphabet recognition system in a small-sized keypad, which can greatly reduce the number of input strokes and the time for inputting a word or phrase.

According to an aspect of the present invention, there is provided an alphabet input device in a small-sized keypad, including: a first keypad part comprising a plurality of buttons each of which is assigned with a symbol extracted from strokes of alphabet characters so that the alphabet characters be input by one of the buttons or a combination of two or more of the buttons; and a second keypad part comprising one or more buttons each assigned with an alphabet character having a high usage frequency.

According to another aspect of the present invention, there is provided an alphabet recognition system in a small-sized keypad, including a control part recognizing alphabet characters by a symbol or symbols, a character or characters, or both input by pressing one or more buttons of the first keypad part, the second keypad part, or both.

According to still another aspect of the present invention, there is provided a character input device in a keypad, including a keypad unit to receive an input of a character input button from a user, the keypad unit including a plurality of character input buttons, a character forming unit to form a character with two inputs of the character input buttons or fewer, and a display unit to display the formed character on the user, wherein the keypad unit receives the input through a touch screen.

According to another aspect of the present invention, there is provided a method of inputting a character in a keypad, including receiving an input of a character input button from a user in a keypad including a plurality of character input buttons, forming a character with two inputs of the character input buttons or fewer, and displaying the formed character on the user, wherein the receiving of the input includes receiving the input through a touch screen.

The above and other aspects will be discussed in detail infra.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects, aspects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a diagram illustrating the arrangement structure of a related-art English keypad with a toggle function;

FIG. 2 is a diagram illustrating the configurations of related-art alphabet input devices with a combination function;

FIGS. 3A and 3B are diagrams illustrating a keypad of an alphabet input device according to an embodiment of the present invention;

FIG. 4 is a graph illustrating statistical data about frequency of alphabet characters in English phrases; and

FIG. 5 is a diagram illustrating a combination tree structure in an alphabet input device according to an embodiment of the present invention.

FIG. 6 is a block diagram illustrating a structure of a character input device according to an embodiment of the present invention.

FIG. 7 is a diagram illustrating a configuration of a keypad including a character input button of a character input device, according to an embodiment of the present invention.

FIG. 8 is a diagram illustrating an example of inputting a character through a character input device according to an embodiment of the present invention.

FIG. 9 is a diagram illustrating another example of inputting a character through a character input device according to an embodiment of the present invention.

FIG. 10 is a diagram illustrating still another example of inputting a character through a character input device according to an embodiment of the present invention.

FIG. 11 is a flowchart illustrating a method of inputting a character in a keypad according to an embodiment of the present invention.

DETAILED DESCRIPTION

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIGS. 3A, 3B and 5 are diagrams illustrating a keypad in an alphabet input device and an alphabet recognition system according to an embodiment of the present invention.

Referring to FIGS. 3A and 3B, the alphabet input device includes a first keypad part and a second keypad part.

The first keypad part includes a plurality of buttons. Each of the buttons is assigned to a symbol extracted from strokes of alphabet characters so that the alphabet characters may be constructed (input) by one of the buttons or a combination of two or more of the buttons. As a non-limiting example, the first keypad part may include seven buttons of ‘-’, ‘|’, ‘.’, ‘(‘,’)’, ‘U’, and ‘V’. It should be noted that the number of buttons of the first keypad part can be adjusted depending on design choice and other needs. It also should be noted that different sets of symbols can be determined and the position of the corresponding buttons can be adjusted.

The second keypad part includes one or more buttons. The button or buttons of the second keypad part are assigned to alphabet characters having high usage frequency. As a non-limiting example, the second keypad part includes five buttons which are assigned to alphabet characters of ‘A’, ‘E’, ‘O’, ‘T’, and ‘I’. It should be noted that the number of buttons of the second keypad part can be adjusted and other needs. It also should be noted that different sets of alphabet characters can be determined as ones having high usage frequency and the position of the corresponding buttons can be adjusted.

The alphabet recognition system includes the first and second keypad parts and a control part. The control part recognizes alphabet characters by a symbol or symbols, a character or characters, or both input by pressing one or more buttons of the first keypad part, the second keypad part, or both. Also, the control part may control the recognized alphabet character or characters to be outputted through an output device.

In an embodiment, as shown in FIG. 3A, the first keypad part may include seven buttons of ‘-’, ‘|’, ‘.’, ‘(‘,’)’, ‘U’, and ‘V’, while the second keypad may include three buttons of ‘A’, ‘E’, and ‘O’. In this case, however, the button ‘O’ may be considered to belong to the second keypad part because ‘O’ is an alphabet character having a high usage frequency as well as considered to belong to the first keypad part because ‘Q’ may be outputted upon a sequential input of ‘O’ and ‘.’.

In an embodiment, the alphabet input devices and the alphabet recognition systems may further include a conversion button part (not shown in the drawings) for converting a small letter into a capital letter and vice versa.

According to the embodiments, alphabets can be input in a hieroglyphic combination manner. Accordingly, unlike the devices and systems with the toggle function, the devices and systems with the hieroglyphic combination function do not require a button arrangement in which a plurality of alphabet characters are grouped into a button and do not require an automatic waiting time and/or a movement button.

According to an embodiment, the number of key buttons constituting a keypad may be set to a particular number, e.g., ten (FIG. 3A) so that the devices and systems can be applied to an existing keypad.

Preferably, the buttons may be arranged in consideration of the usage frequency of respective alphabets and a predefined combination tree structure. Also, one character may be assigned to one button to have an intuitive interface.

In a modified embodiment, a character having a high usage frequency, such as T (FIG. 3B), may be assigned to one of the two blank keys.

It is noted, however, that the present invention is not be limited to the arrangement forms.

FIG. 4 is a statistical data about frequency of alphabet characters used in English phrases. As shown in FIGS. 4, E, T, A, O, and I have higher usage frequencies than other alphabet characters. At least one of the alphabet characters having higher usage frequencies may be designed to be inputted by one-click. Minimizing the number of click for inputting such high frequency alphabet characters, preferably coupled with the hieroglyphic combination function, enables users to input alphabet characters in a more convenient and efficient manner.

As discussed above, the present invention is not limited thereto. Various modification can be made depending on the design choice and other needs. For instance, as illustrated in FIGS. 3A, 3B and 5, only E, A, and O among E, T, A, O, and I may be inputted by one-click (T and I may be inputted by a combination of symbols).

In this case, the other alphabet characters may be inputted by a combination of buttons of the first and second keypad parts. For example, T can be inputted by the combination of ‘-’ and ‘|’, L can be inputted by the combination of ‘|’ and ‘-’, F can be inputted by the combination of ‘-’, ‘|’ and ‘.’.

In case T is assigned to a blank key as shown in FIG. 3B, T may be inputted by one-click. Even in this case, it is possible to design the device so that T can be inputted also by a combination characters.

FIG. 5 is a diagram illustrating a combination tree structure of each alphabet in an alphabet input device according to an embodiment of the present invention.

As illustrated in FIG. 5, the control part recognizes a sequential input of ‘|’, ‘)’, and ‘)’ as ‘B’, an input of ‘(’ as ‘C’, and a sequential input of ‘|’, and ‘)’ as ‘D’.

The control part recognizes a sequential input of ‘|’ and ‘.’ as ‘F’, a sequential input of ‘(’ and ‘.’ as ‘G’, and a sequential input of ‘|’, ‘|’ and ‘.’ as ‘H’.

The control part recognizes a sequential input of ‘|’, and ‘.’ as ‘I’, a sequential input of ‘U’ and ‘.’ as ‘J’, and a sequential input of ‘|’ and ‘(’ as ‘K’.

The control part recognizes a sequential input of ‘|’, and ‘-’ as ‘L’, a sequential input of ‘|’, ‘|’ and ‘V’ as ‘M’, and a sequential input of ‘|’ and ‘V’ as ‘N’.

The control part recognizes a sequential input of ‘|’, ‘|’ and ‘)’ as ‘P’, a sequential input of ‘O’ and ‘.’ as ‘Q’, and a sequential input of ‘|’, ‘)’, and ‘.’ as ‘R’.

The control part recognizes a sequential input of ‘(’ and ‘)’ as ‘S’, a sequential input of ‘-’ and ‘|’ as ‘T’, a sequential input of ‘V’ and ‘.’ as ‘Y’, and a sequential input of ‘-’, ‘.’, and ‘-’ as ‘Z’.

The control part recognizes double inputs of ‘V’ within a predetermined time as ‘W’. If the double click is not performed within a predetermined time, e.g., 0.2 seconds, each click is recognized as ‘V’.

The control part recognizes double inputs of ‘U’ within a predetermined time as ‘X’. If the double click is not performed within a predetermined time, e.g., 0.2 seconds, each click is recognized as ‘U’.

The control part recognizes and displays the input of ‘A’ and ‘E’ as it is, respectively.

The control part recognizes an input of ‘O’ followed by an input of any other button except ‘.’ as ‘O’.

The control part recognizes an input of ‘U’ within a predetermined time or followed by an input of any other button except ‘.’ as ‘U’. The control part recognizes an input of ‘V’ within a predetermined time or followed by an input of any other button except ‘.’ as ‘V’.

As shown in FIG. 3B, if T is assigned to one of key buttons of the keypad, the control part recognizes an input of ‘T’ as ‘T’. That is, a user is not required to sequentially click ‘-’ and ‘|’ buttons in order to input ‘T’. As discussed above, in this case, it is possible to design so that T can be inputted also by a combination of symbols (e.g., ‘-’ and ‘|’).

The control part recognizes the inputted alphabet character or characters and outputs the recognized alphabet character or characters through an output device.

As described above, the combination tree structure of alphabet characters defined by the hieroglyphic combination method according to an embodiment of the present invention can fundamentally solve the limitations of the related-art systems.

In an embodiment, the devices and systems may further provide a function to delete an inputted character efficiently. That is, when a user wants to delete an inputted character, the user may move to a previous combination state and, optionally, make another combination by clicking a button or buttons. For example, ‘B’ turns to ‘D’ through deletion of ‘)’. In this case, if ‘.’ is inputted, ‘D’ turns to ‘R’.

The devices and systems using the combination input manner coupled with consideration of usage frequency according to the present invention require less input strokes and take shorter time than those using the related-art toggle input manner. For example, assume that a word ‘DEFENCE’ is inputted. While the toggle type devices and systems require eighteen input strokes including a movement button, the combination type devices and systems according to the present invention require only eleven input strokes.

FIG. 6 is a block diagram illustrating a structure of a character input device 600 according to an embodiment of the present invention. The character input device 600 may include a keypad unit 610, a character forming unit 620, and a display unit 630.

The keypad unit 610 may receive, from a user, an input of a character input button of a keypad that includes a plurality of character input buttons used to input characters. The keypad unit 610 may receive the input through a touch screen, and the touch screen may include any type of touch screen, for example, a capacitive touch screen and a resistive touch screen.

The character input buttons may be used in inputting characters, and may include buttons bearing basic letters of the alphabet such as A, C, E, I, and O, and symbols used to form characters by combinations with the basic letters of the alphabet. The character input buttons may further include at least one of a ‘delete’ button, a ‘close window’ button, a ‘line spacing’ button, a ‘caps lock’ button, and a space button.

According to the exemplary embodiments of the present invention, a character may be formed with two inputs of character input buttons or fewer through the keypad unit 610. Hereinafter, one input may be referred to as a first input, and another input may be referred to as a second input. After a user proceeds with a first input, a character input button for a second input may be displayed distinguishably for ease of viewing, for example, in bold or with a different color. In this instance, a character inputted with the first input may be combined with a character inputted with the second input to form a letter of the alphabet or a character.

The character input device 600 may be applied to an electronic device, in particular, a touch screen-based electronic device. The first input and the second input may be implemented by pressing the character input button. The first input and the second input may be implemented by touching and dragging the character input button. For example, while touching a desired character input button as the first input, the touched character input button may be dragged onto a desired character input button for the second input, and the touch may be released from the desired character input button for the second input.

A further detailed description will be provided in the following.

The character forming unit 620 may form a character by a combination of the identified inputs of the character input buttons. The character may be formed with two inputs or fewer. The character may be formed by one input or a combination of two inputs. The formed character may be displayed to the user through the display unit 630.

FIG. 7 is a diagram illustrating a configuration of a keypad 700 including a character input button of a character input device according to an embodiment of the present invention. The keypad 700 may perform a character input function in an electronic device, for example, a mobile phone, a smart phone, a tablet personal computer (PC), and the like. The keypad 700 may be provided on a display of an electronic device to deliver a command to the electronic device or to transmit a message to another electronic device.

The keypad 700 may include character input buttons, for example, thirteen character input buttons, to be adapted to a small-sized electronic device. The keypad 700 may further include a selection input button, for example, a ‘delete’ button, a ‘close window’ button, a ‘line spacing’ button, a ‘caps lock’ button, and a space button. The arrangement of the character input buttons of the keypad 700 is not limited to a specific pattern, and a frequently used input button 710 may be placed at the center of a particular keypad configuration and a combining input button may be placed around the frequently used input button 710.

A character corresponding to the character input button of the keypad 700 and a character formed substantially as a letter may be displayed on the user through the display unit 630 of FIG. 6. Displaying may be implemented in real time based on an input by the user. As an example, the keypad 700 may be displayed in an electronic device through the display unit 630 for an input by the user. The display unit 630 may display the keypad 700.

Hereinafter, examples of forming a character are described with reference to FIGS. 8 through 10. In said examples, a first input and a second input may be identified through the keypad unit 610 of the character input device 600, and a character to be displayed through the display unit 630 may be formed through the character forming unit 620.

FIG. 8 illustrates an example of forming a character by a combination of characters corresponding to character input buttons according to an embodiment of the present invention.

Referring to FIG. 8, a keypad may correspond to the keypad 700 of FIG. 7. While an ‘I’ button 810 is pressed by a finger 820 of a user, character input buttons 811 through 814 that may be used to form a new character by a combination with the ‘I’ button 810 may be displayed in such a distinguishable form that characters represented on character input buttons 811 through 814 are displayed in bold. Here, the keypad 700 may correspond to a touch screen-based input system, and the finger 820 of the user may be replaced with an instrument such as, for example, a stylus, based on a type of a touch screen.

When the finger 820 of the user pressing the ‘I’ button 810 is taken off, a character ‘I’ may be inputted and may be displayed on the user through the display unit 630. When the finger 820 being pressed is released from the ‘I’ button 810, the characters represented on character input buttons 811 through 814 may be displayed in bold. Such an action is performed to emphasize a character input button available for the second input since the input of the ‘I’ button 810 may be easily identified as the first input. For ease of identifying the second input, the character input buttons 811 through 814 may be displayed distinguishably with a different color. When one of the character input buttons 811 through 814 is inputted, the character other than ‘I’ may be displayed through the display unit 630.

Alternatively, while touching the ‘I’ button 810 as the first input, the touched ‘I’ button 810 may be dragged onto a desired character input button for the second input among the character input buttons 811 through 814 with the finger 820 of the user, and the finger 820 of the user may be taken off from the desired character input button. When the touch is released, the first input and the second input may be identified and a character formed by a combination of the first input and the second input may be displayed through the display unit 630.

For example, when the ‘I’ button 810 is inputted as the first input and the button ‘-’ 811 is inputted as the second input, a character ‘L’ may be formed by a combination of ‘I’ and ‘-’. When the ‘I’ button 810 is inputted as the first input and the ‘C’ button 812 is inputted as the second input, a character ‘K’ may be formed by a combination of ‘I’ and ‘C’. When the ‘I’ button 810 is inputted as the first input and the ‘O’ button 813 is inputted as the second input, a character ‘D’ may be formed by a combination of ‘I’ and ‘O’. When the ‘I’ button 810 is inputted as the first input and the ‘V’ button 814 is inputted as the second input, a character ‘N’ may be formed by a combination of ‘I’ and ‘V’. The corresponding character may be displayed through the display unit 630. This intuitive combination may ease the character input for the user.

FIG. 9 illustrates another example of forming a character through a character input device according to an embodiment of the present invention. Similar to FIG. 8, a character may be derived from a combination of characters on the keypad 700 being input with the first input and the second input, and may be displayed.

Referring to FIG. 9, when a ‘P’ button is inputted with a finger 920 of a user, the input of the ‘P’ button 910 may be identified to be the first input. When the finger 920 of the user is taken off from the ‘P’ button 910, a character ‘P’ may be identified.

When the first input of the ‘P’ button 910 is identified, a ‘O’ button 911 and a ‘.’ button 912 may be displayed for the second input. The ‘O’ button 911 and the ‘.’ button 912 may be displayed distinguishably in bold or with a different color for ease of identifying the second input. While touching the ‘P’ button 910 as the first input with the finger 920 of the user, the touched ‘P’ button 910 may be dragged onto the ‘O’ button 911, and when the touch is released, the input of the ‘O’ button 911 may be identified to be the second input. A character ‘B’ may be formed by a combination of ‘P’ and ‘O’, and may be displayed through the display unit 630.

While touching the ‘P’ button 910 as the first input with the finger 920 of the user, the touched ‘P’ button 910 may be dragged onto the ‘.’ button 912, and when the touch is released, the input of the ‘.’ button 912 may be identified to be the second input. A character ‘R’ may be formed by a combination of ‘P’ and ‘.’, and may be displayed through the display unit 630.

Although this exemplary embodiment shows the first input and the second input based on a touch-and-drag operation, the present invention is not limited to such an operation. For example, after the first input is identified, the subsequent second input may be identified.

According to the exemplary embodiments of the present invention, a new layout for a keypad may minimize a number of strokes required for inputting an alphabet character.

FIG. 10 illustrates still another example of forming a character through a character input device according to an embodiment of the present invention. Referring to FIG. 10, a keypad may correspond to the keypad 700 of FIG. 7, and a finger 1020 of a user may be replaced with an instrument such as, for example, a stylus, based on a type of a touch screen.

When a ‘∥’ button 1010 is input with the finger 1020 of the user, the input of the ‘∥’ button 1010 may be identified to be the first input, and a ‘.’ button 1011 and a ‘V’ button 1012 may be displayed for the second input. The ‘.’ button 1011 and the ‘V’ button 1012 may be displayed distinguishably for ease of the second input.

For example, while touching the ‘∥’ button 1010 as the first input with the finger 1020 of the user, the touched ‘∥’ button 1010 may be dragged onto the ‘.’ button 1011, and when the touch is released, the input of the ‘.’ button 1011 may be identified to be the second input. A character ‘H’ may be formed by a combination of ‘∥’ and ‘.’.

While touching the ‘∥’ button 1010 as the first input with the finger 1020 of the user, the touched ‘∥’ button 1010 may be dragged onto the ‘V’ button 1012, and when the touch is released, the input of the ‘V’ button 1012 may be identified to be the second input. A character ‘M’ may be formed by a combination of ‘∥’ and ‘V’.

In this way, various alphabet characters may be formed, and the first input and the second input may be identified through the keypad unit 610 of the character input device 600 and a character to be displayed through the display unit 630 may be formed through the character forming unit 620.

Since the ‘.’ button corresponds to a button used most frequently in the keypad when forming a character, the ‘.’ button may be placed at the center of the keypad to minimize a movement distance between buttons.

The second input of the ‘.’ button may form a character ‘G’ with the first input of the ‘C’ button, a character ‘Q’ with the first input of the ‘O’ button, a character ‘F’ with the first input of the ‘T’ button, and a character ‘Y’ with the first input of the ‘V’ button.

According to the exemplary embodiments of the present invention, a small letter may be formed absent the ‘caps lock’ button function being turned off. When the ‘I’ button is inputted as the first input and the ‘.’ button is inputted as the second input, a character ‘i’ may be formed, and when the ‘U’ button is inputted as the first input and the ‘.’ button is inputted as the second input, a character ‘j’ may be formed.

In another example, a character may be formed with a double click as the first input and the second input. A character ‘W’ may be formed with a double click of the ‘∥’ button, a character ‘X’ may be formed with a double click of the ‘I’ button, and a character ‘Z’ may be formed with a double click of the ‘-’ button. The corresponding character may be displayed on the user through the display unit 630. Although not shown, a character ‘S’ may be formed when the ‘C’ button is inputted as the first input and the ‘O’ button is inputted as the second input.

According to the exemplary embodiments of the present invention, symbols as well as alphabet characters may be formed and displayed. For example, when the ‘C’ button is inputted as the first input and the button ‘O’, is inputted as the second input, a question mark ‘?’ may be formed and displayed. When the ‘-’ button is inputted as the first input and the button is inputted as the second input or vice versa, a comma ‘,’ may be formed and displayed. In the exemplary embodiment of the keypad 200 of FIG. 2, selection input buttons rather than character input buttons may be used to form a symbol. When the ‘-’ button and the ‘.’ button are inputted while the ‘caps lock’ button is pressed, a single quotation mark “'” may be formed and displayed.

Although the present disclosure has been described with exemplary embodiments, various exemplary embodiments that may be implemented by the character input method of the present invention not disclosed in the description may be contemplated. It is intended that the present disclosure encompass such exemplary embodiments as falling within the scope of the appended claims.

According to the exemplary embodiments of the present invention, a number of input strokes may be reduced. For example, a word ‘The’ may be formed by a combination of ‘T’, ‘∥’, ‘.’, and ‘E’, however, the input of ‘.’ may be omitted. The word ‘The’ may be only recognized by inputs of ‘T’, ‘∥’, and ‘E’. Here, the ‘caps lock’ button may be used to input small letters and capital letters.

FIG. 11 is a flowchart illustrating a method of inputting a character in a keypad according to an embodiment of the present invention. The method may be performed by each component of the character input device 600 of FIG. 6, and may be simplified or subdivided.

In operation 1110, the character input device 600 may receive an input of a character input button from a user through a keypad including a plurality of character input buttons. The character input device 600 may receive the input through a touch screen, and the touch screen may include any type of touch screen, for example, a capacitive touch screen and a resistive touch screen.

The character input buttons may be used in inputting alphabet characters, and may include buttons bearing basic letters of the alphabet A, C, E, I, and O, and symbols used to form characters by combinations with the basic letters of the alphabet.

In operation 1120, the character input device 600 may form a character with two inputs of the character input buttons or fewer. The character input device 600 may form a character by one input or a combination of two inputs.

In operation 1130, the character input device 600 may display the formed character on the user. Displaying may be implemented in real time based on an input by the user. As an example, the keypad including the character input buttons may be displayed in an electronic device through the display unit 630 for an input by the user.

The exemplary embodiments described with reference to FIGS. 7 through 10 may be referred to for any disclosures of the character input method omitted in the description of FIG. 11.

According to the exemplary embodiments of the present invention, the alphabet input device in a small-sized keypad may input all the alphabet characters with two inputs of keys or fewer based on the intuitive understanding of the user. Contrary to conventional input of alphabet characters assigned to the same key, the alphabet input method of the present invention may improve an input efficiency by eliminating the need to pause for a predetermined period of time or to press a space key to input a subsequent alphabet character.

The units described herein may be implemented using hardware components, software components, or a combination thereof. For example, a processing device may be implemented using one or more general-purpose or special purpose computers, such as, for example, a processor, a controller and an arithmetic logic unit (ALU), a digital signal processor, a microcomputer, a field programmable array (FPA), a programmable logic unit (PLU), a microprocessor or any other device capable of responding to and executing instructions in a defined manner. The processing device may run an operating system (OS) and one or more software applications that run on the OS. The processing device also may access, store, manipulate, process, and create data in response to execution of the software. For purpose of simplicity, the description of a processing device is used as singular; however, one skilled in the art will appreciate that a processing device may include multiple processing elements and multiple types of processing elements. For example, a processing device may include multiple processors or a processor and a controller. In addition, different processing configurations are possible, such as parallel processors.

The character input methods according to the above-described exemplary embodiments of the present invention may be recorded in computer-readable media including program instructions to implement various operations embodied by a computer. The media may also include, alone or in combination with the program instructions, data files, data structures, and the like. Examples of computer-readable media include magnetic media such as hard discs, floppy discs, and magnetic tape; optical media such as CD ROM discs and DVDs; magneto-optical media such as floptical discs; and hardware devices that are specially configured to store and perform program instructions, such as read-only memory (ROM), random access memory (RAM), flash memory, and the like. Examples of program instructions include both machine code, such as produced by a compiler, and files containing higher level code that may be executed by the computer using an interpreter. The described hardware devices may be configured to act as one or more software modules in order to perform the operations of the above-described exemplary embodiments of the present invention, or vice versa.

Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims. 

1. A character input device in a keypad, comprising: a keypad unit to receive an input of a character input button from a user, the keypad unit comprising a plurality of character input buttons; a character forming unit to form a character with two inputs of the character input buttons or fewer; and a display unit to display the formed character on the user, wherein the keypad unit receives the input through a touch screen.
 2. The character input device of claim 1, wherein the keypad unit includes the character input buttons corresponding to characters ‘-’, ‘∥’, ‘.’, ‘I’, ‘C’, ‘O’, ‘U’, ‘V’, ‘A’, ‘E’, ‘P’, ‘O’, and ‘T’, the character is formed by the input character alone or a combination of the input characters through the character forming unit, and the character formed by the combination of the input characters is determined based on a first input and a second input.
 3. The character input device of claim 2, wherein a character ‘B’ is formed with the first input of the ‘P’ button and the second input of the ‘O’ button, and a character ‘R’ is formed with the first input of the ‘P’ button and the second input of the ‘.’ button.
 4. The character input device of claim 2, wherein a character ‘D’ is formed with the first input of the ‘I’ button and the second input of the ‘O’ button, a character ‘K’ is formed with the first input of the ‘I’ button and the second input of the ‘C’ button, a character ‘N’ is formed with the first input of the ‘I’ button and the second input of the ‘V’ button, and a character ‘L’ is formed with the first input of the ‘I’ button and the second input of the ‘-’ button.
 5. The character input device of claim 2, wherein a character ‘M’ is formed with the first input of the ‘∥’ button and the second input of the ‘V’ button, and a character ‘H’ is formed with the first input of the ‘∥’ button and the second input of the button.
 6. The character input device of claim 2, wherein the second input of the ‘.’ button forms a character ‘G’ with the first input of the ‘C’ button, a character ‘Q’ with the first input of the ‘O’ button, a character ‘F’ with the first input of the ‘T’ button, a character ‘Y’ with the first input of the ‘V’ button, a character ‘i’ with the first input of the ‘I’ button, a character ‘j’ with the first input of the ‘U’ button, and a character ‘,’ with the first input of the ‘-’ button.
 7. The character input device of claim 2, wherein the character is formed with a double click as the first input and the second input, and a character ‘W’ is formed with the double click of the ‘∥’ button, a character ‘X’ is formed with the double click of the ‘I’ button, and a character ‘Z’ is formed with the double click of the ‘-’ button.
 8. The character input device of claim 2, wherein a character ‘S’ is formed with the first input of the ‘C’ button and the second input of the ‘O’ button, and a character ‘?’ is formed with the first input of the ‘O’ button and the second input of the ‘.’ button.
 9. The character input device of claim 2, wherein the keypad unit displays a character input button available for the second input distinguishably when the keypad unit identifies the first input.
 10. The character input device of claim 2, wherein the first input and the second input are based on a touch-and-drag operation, and the first input is implemented by touching a character input button, and the second input is implemented by dragging the touched character input button and releasing the touch.
 11. A method for inputting a character in a keypad, the method comprising: receiving an input, from a user, of a character input button in a keypad comprising a plurality of character input buttons; forming a character with two inputs of the character input buttons or fewer; and displaying the formed character on the user, wherein the receiving of the input comprises receiving the input through a touch screen.
 12. The method of claim 11, wherein the character input buttons include buttons corresponding to characters ‘-’, ‘∥’, ‘.’, ‘I’, ‘C’, ‘O’, ‘V’, ‘A’, ‘E’, ‘P’, ‘O’, and ‘T’, the character is formed by the input character alone or a combination of the input characters, and the character formed by the combination of the input characters is determined based on a first input and a second input. 